•New cellulose based adsorbents for boron (III) was prepared by radiation grafting.•The adsorbent (CVN) reached an adsorption capacity of 12.4 mg g−1 at pH 6.•The adsorption process obeys the Langmuir isotherm model.•The uptake of boron (III) was enhanced in saline solutions.A novel cellulose-based microsphere containing glucamine groups, referred as CVN, was successfully synthesized by radiation-induced graft polymerization of 4-vinylbenzyl chloride onto cellulose microspheres and subsequent functionalization with N-methyl-d-glucamine. The adsorption by CVN for boron (III) from aqueous solutions was evaluated systematically by batch adsorption technique. Langmuir models could fit well with the adsorption behavior of CVN. The CVN adsorbents exhibited a high adsorption capacity up to 12.4 mg g−1 towards boron (III) over the wide pH range of 5–8. After the addition of chloride salts, the boron uptake of CVN was enhanced that was attributed to the compensation of the surface charge generated by boron (III) adsorption leading to favor the adsorption. At high concentrations of salts, the ionic strength and different salts have no effect on the adsorption of boron(III). This work provides a new sustainable, cost effective material as a promising specific adsorbent for the removal of boron (III) from saline solutions.

Thermal stability of ionic liquids (ILs) is of great significance for their applications in dissolving cellulose at elevated temperature. A novel ionic liquid, 1-allyl-3-methylimidazolium chloride ([Amim]Cl), was found to be a powerful solvent for cellulose. However, the study about long-term isothermal stability, thermal decomposition mechanism and decomposition products of [Amim]Cl are scarce. Herein, we studied the thermal stability and degradation mechanism of [Amim]Cl using isothermal thermogravimetric analysis (TGA) experiments and density functional theory (DFT) calculations. The weight loss of [Amim]Cl at 100 °C under air atmosphere within 15 days was only 1.9% and [Amim]Cl after long-term heating also had dissolving capability of cellulose, indicating that [Amim]Cl has high thermal stability and can be long-term used at the dissolving temperature of cellulose. Both TGA experiments and DFT calculations revealed [Amim]Cl decomposed along two channels and the main pyrolysis products of the proposed mechanisms were detected using thermogravimetric technique coupled with mass spectrometry (TGA–MS).

This paper reports a homogeneous modification of microcrystalline cellulose (MCC) in ionic liquids via radiation-induced grafting. Thermosensitive poly (N-isopropylacrylamide) (PNIPAAm) was successfully grafted onto MCC in 1-butyl-3-methylimidazolium chloride ([Bmim]Cl) ionic liquid using γ-ray irradiation technique at room temperature. The grafting yield (GY) increased with dose up to 40 kGy, while decreased slightly with dose rate from 22 to 102 Gy/min. The results of TGA indicated that cellulose grafted PNIPAAm (cellulose-g-PNIPAAm) had higher thermal stability than that of ungrafted regenerated cellulose (reg-cellulose). The crystalline structure of original MCC was largely destroyed during the dissolution process according to the XRD profiles, and grafting PNIPAAm onto cellulose further decreased the intensity of crystallinity. SEM showed that reg-cellulose and cellulose-g-PNIPAAm films displayed dense and homogeneous morphology. Moreover, the resulting cellulose-g-PNIPAAm exhibited obvious thermal sensitivity with a lower critical solution temperature around 35 °C, which was observed from the swelling behavior in water at different temperatures.

Long and continuous silver nanowires within multi-walled carbon nanotubes (MWCNTs) were formed after irradiating the suspension of MWCNTs-silver nitrate solution in the presence of 2-propanol due to radiation-induced reduction of silver ions. Observation using transmission electron microscopy showed that the silver nanowires could be up to 2 μm in length, with a well-oriented structure. The conditions for growing silver nanowires within MWCNTs were investigated and the possible filling mechanism was proposed. The length of silver nanowires was influenced by ambient temperature of radiation and the presence of 2-propanol was crucial for the formation of silver nanowires within MWCNTs.

Dicyclohexano-18-crown-6 (DCH18C6) aqueous solution was irradiated using 60Co source and precipitates containing yellow transparent blocks (PA) and powders (PB) were obtained. TGA analysis confirms that both PA and PB have higher thermal stability than DCH18C6. Both DSC and GPC results suggest that PA might be oligomer and PB were ultrahigh molecular weight polymers. The FTIR spectra indicate that both PA and PB have similar chemical structures containing carboxyl and hydroxyl groups. By using scavengers, it was found that the formation of PA and PB is attributed to the radiation-induced radical polymerization of DCH18C6, and ·OH radical produced by water radiolysis might be a critical species for the formation of PA and PB. These studies help to understand the radiation chemistry behavior of DCH18C6 in the reprocessing of nuclear fuel.Highlight► Dicyclohexano-18-crown-6 (DCH18C6) aqueous solution was irradiated by 60Co source. ► Transparent yellow blocks (PA) and powders (PB) precipitates were obtained. ► PA and PB are determined as oligomers and ultra-high molecular weight polymers, respectively. ► The formation mechanism of precipitates is the radiation-induced radical polymerization. ►·OH radical from water radiolysis is a critical species for the formation of precipitates.

Reaction rate constants of crown ethers (12-crown-4, 15-crown-5, 18-crown-6) and their analogs 1,4-dioxane (6C2) with some important oxidative radicals, hydroxyl radical (OH), sulfate radical (SO4−) and nitrate radical (NO3), were determined in various aqueous solutions by pulse radiolysis and laser photolysis techniques. The reaction rate constants for 6C2 and crown ethers with OH and SO4− increase with the number of hydrogen atoms in the ethers, indicating that the hydrogen-atom abstraction is a dominant reaction between crown ethers and these two radicals. The presence of cations in solution has negligible effect on the rate constants of crown ether towards OH and SO4−. However, for the NO3, the rate constants are not proportional to the number of hydrogen atoms in ethers, and 12-crown-4 (12C4) is the most reactive compared with other crown ethers. Except 12C4 and 6C2, the cations in the aqueous solution affect the reactivities of 15-crown-5 (15C5) and 18-crown-6 (18C6). The cations with high binding stability for crown ether would improve the reactivity of 15C5. For the studied crown ethers, the reaction rate constants of these oxidative radicals have the order OH>SO4−>NO3. Furthermore, the formation of radicals after the reaction of crown ethers with sulfate radical could be observed in the range of 260–280 nm using laser photolysis and pulse radiolysis. This is the first report on the kinetic behavior of crown ethers with NO3, and it would be helpful for the understanding of stability of crown ethers in the processing of spent nuclear fuel.Highlights► The rate constants of NO3 and SO4− towards various crown ethers in aqueous solution were determined for the first time. ► The rate constants of these radicals towards crown ethers have the order OH>SO4−>NO3. ► Hydrogen atom abstraction is the dominant reaction between these radicals and crown ethers. ► The binding capacity of crown ethers with cations in solution will affect k (NO3+ ethers).